Well-drilling apparatus



Nov. 18, 1930. w. SHELDON WELL DRILLING APPARATUS Filed May 5, 'l926 2 Shee'EsSheet 1 Nov. 18, 1930. w. SHELDON WELL DRILLING APPARATUS- 2 Sheets-Sheet 2 Filed May 5 192 Patented Nov. 18, 1 930 PATENT OFFICE -'WALDO SHELDON, OF SOUTH NOBWALK, CONNECTICUT WELL-DRILLING APPARATUS Application filed May 5, 1926. Serial No. 106,850.

This invention relates particularl to oil well drilling apparatus of the type isclosed in prior pendm feed of the dril is governed through the 5 operation of a power cylinder or cylinders. With these machines it has been the practice for the driller to watch the rotary table which turnsthe drill and to ease off the pressure or apply greater. pressure as occasion requires. 1 This demands practically constant watchfulness and means that any lack of attention may result in injury or breakage of parts. Special objects of the present invention are to automatically control the action of the 15 drill and to regulate the pressure so as to maintain the drill substantially continuously at the proper drilling speed. Related objects are to enable the driller to arbitrarily control the drill independently of any automatic action and to enable the quick settin of the automatic control to different desired drilling speeds.

A further object of the invention is to effect certain improvements in the hydraulic cylinder by which the'pressure is applied to the drill stem.

The foregoing and other desired objects are attained in this invention by certain novel features of construction, combination and relation of parts as hereinafter described and broadly claimed.

The drawings accompanying and forming part of this specification illustratea simple, practical embodiment of the 1!.vent1on, wherein a v Figure 1 is a side elevation and part 'dia ammatic view of the drill with automatic and hand control. Figure 2 is cross sectional view ofv the pressure feed valve.

of the hydraulic cylinder structure.

re 1 the rotary table, is shown at 5 In Figu driven by gearing 6 from shaft 7 The hydrauliccylinder 8 is illustrated as of annular construction concentrically supported below the table. Figure3 shows more in detail how this cylinder is made up of outer and inner concentric walls 9, 10 forming between them an annular chamber inwhich applications wherein themovements to a accessible through Figure 3 is an enlarged part sectional view drill stem without with the rotation of the drill stem by the operates the annular piston head 11 connected with the upwardly extending annular piston rod 12. This tubular piston rod through upwardly anddownwardly acting thrust bearings 13, 1 can impart .corresponding 55 drive sleeve 15 which is slidingly keyed in the table at 16 and carries clamping means indicated generally at 17 for gripping the drill pipe 18. v The piston head is shown as packed by a 00 plurality of substantially rectangular cross section rubber rings 19 seated in open recesses 20 at the opposite sides of the annular piston and expanded by a pressure plate '21 of substantially U-shape cross section fitting 05 over the recessed sides of the piston head. This circular ring expander-is shown as adjustably secured by bolts 22 extending through the central part of the ring into the central portion of the head, which bolts are ports 23 provided for the purpose in the lower annular cylinder head 24. These ports may be ordinarily closed by plugs 25 and one or more of such ports may e utilized for entry of the power fluid by means of the lower pipe connection 26. The upper cylinder head is shown as packed where the tubular piston rod emerges therefromby similar elastic packing rings 27 supported in an open seat 28 at the inner circumference of said head, the upper packing ring being engaged by an expander 29 which can be forced down by a screw ring 30. To further seal the piston in the cylinder, packing rings are shown at 31 inter- 8 .power fluid is entered into the top of the cylinder above the piston head through a connection 32.. It will be evident from the foregoing that by controlling admission and exhaust of the power fluid through piping 26and 32, pressure may be applied. to raise and lower the in any way interfering table. 7

Water under pressure is employed as the power fluid in the present disclosure and the control isshown as efiected by a special valve indicated This valve is ure 2 as a casing having an inlet port 34 between two piston valves 35, 36 controlling flow throu 11 ports 37, 38 to the upper and lower supp y pipes 32, 26. The valve casing also has an exhaust port 39 from which return piping 40 extends to a supply tank 41.

pump is indicated at 42 for taking water from this tank through iping 43, the pressure side of the pump being connected by piping 44 with the supply port 34 of the va ve.

The piston valves 35, 36 of the control mechanism are shown connected by a stem 45 which is en aged at 46 with one end of generally at 33 in Figure 1.

a hand lever 4 pivoted at 48. It will be seen that by raising this hand lever the valve stem 45 will be lowered to admit pressure from port 34 past piston valve 36 to port 38 and through pi ing 26 to the lower end of the power cyl n er, and conversely, that the lowering of the hand lever will lift the valve stem to open port 37 and admit pressure to the to of the power cylinder. Consequently, t e power piston and hence the drill pipe gripped in the drive sleeve connected with said piston will be raised and lowered as the hand lever 47 is raised and lowered.

A scale and pointer mechanism 49 is indicated at the end of the hand lever to gage the adjustments and a hand screw is shown at 50 engaged on a screw stem 51 connected with the lever and extending through a guide 52 which enables the hand lever to be set at-any desired adjustment.

By means of the control valve it will be seen that the driller can raise or lower the drill bit at will. Usually, the operation of the turntable is observed and if it slows down, due to the bit encountering a harder stratum, the drill is lifted to relieve theweight on the bit and conversely, if the table speeds up, pressure is applied to increase the load and bring the table back to the proper drilling speed. This control requires the constant attention of the driller, is uncertain and always involves a certain amount of lag between the time when the change actually occurs and the time when the drillerv after noticing the change has had opportunity to apply corrective measures. These uncertainties and .delaysare eliminated in the present invention by automatically governing the pressure applying mechanism from the speed of rotation of the shafting which drives the table.

In the present disclosure the automatic governor is shown as a ball governor 53 driven from the sprocket gearing 54 and bevel gearing 55 from the main drive shaft. This governor is shown as having its movable collar 56 revolubly connected with an upright linkv 57 which in turn is connected with the hand lever of the control valve.

illustrated in detail in F ig- The connection with the hand lever is shown as made by means of a hand nut 58 engaged on a screw stem 59 carried by the lever, the link being slotted at 60 so that it may either slide freely over the screw stem or else be clamped rigidly to the hand lever means of the hand screw.

With the hand screw loosened. it will be seen that the hand lever of the, control valve may be raised and lowered free of any control from the governor. With the hand screw tightened, however, it will be clear that the hand lever will be shifted'by the governor and the application of the raising and lowering power e thereby given over to the automatlc governor. With the proper drilling speed known, the control handle may be set .to provide the drilling force suited-to that partlcular speed and the governor be then placed in control for that speed by simply turning the hand screw to clamp the connecting link to the hand lever. The governor thus placed in control senses any changes in speed in the drive shaft before they would be perceptible to the driller and operates immediately to offset the result of such changes and to restore the rotary at once to the s eed of operation for which the control has een set. The slowing down of the governor causes the balls to approach the center and to lift the movable collar to which they are connected. corresponding lift is thereby imparted to the hand lever through the medium of the releasable connecting link. As the balls fly apart with an increase in speed, the collar is lowered and the hand lever is correspondingly lowered. Hence if the table starts to slow down, the control valve is operated to lift the drill and if the table starts to speed up, the control valve is operated to lower or to apply more pressure to the drill.

Thus in both instances the turntable is quickly and almost immediately brought back to the predetermined desired drilling speed, making the machine more effective, faster in operation and at the same time protecting thedrill bit and pipe from overstrain. If desired, a speedometer or revolution counter may be applied to the drive shaft so that the driller may know exactly at what speed the drive shaft and table are turning and set the automatic control accordingly.

To allow an automatic normal rate of feed of the drill, the control valve is shown provided with a bleed 61 arranged to permit the power fluid to. slowly escape from the lower end of the cylinder and hence to permit the piston to automatically sink at a predetermined slow rate, such rate depending upon the position at which the lower valve member is left by the control handle. Thus there is provided, in addition to the means for maintaining the rotary table at a predetermined drilling speed, means for automatically feeding the drill at a prederotating the drlll, hydraulic power mechatel-mined normal drilling s ed. The driller may therefore set the mac 'ne for a certain desired normal rate of feed and then rely on the governor to take care of any abnormal or unusual formations and to return the 'drill back to the normal feed after the formation changes have been countered and taken care of.

What is claimed is:

1. In well drilling apparatus, a table for nism for con-trolling feed of the drill,a control valve for said hydraulic power mechanism and a speed governor associated with the table and adapted to exercise control over said valve.

2. In well drilling apparatus, a table for i table, a power cylinder, connections actuated the effect of said power cylinder and thereby for applying the lifting and lowering forces of said cylinder to a drill rotated by the table, a control valve operable to govern automatic means dependent on the speed of operation of the table for automatically controlling said valve.

4. In well drilling apparatus, a rotary table, a power cylinder, connections actuated thereby for applying the lifting and lowering forces of said cylinder to a'drill rotated by the table, a control valve operable to govern the effect of said powerv cylinder and automatic means dependent on the speed of operation of the .table for automatically controlling said valve, said control valve having means which can be set to enable the same to effect a predetermined normal feed of the drill and the automatic control means being adapted tovary the feed from the set normal 'feed according to formation encountered and to return the feed back to the normal when the formation permits.

5. In well drilling apparatus, means for rotating a drill stem, hydraulic power mechanism for feeding the drill stem, valve means for governing said hydraulic feed mechanism and means dependent on the s eed of rotation of the drill stem for automatically actuating said valve means.

6. In well drilling apparatus, means for rotating a drill stem, hydraulic power mechanism for feeding thedrill stem, valve means for governing said hydraulic feed mechanism and means dependent on the speed of rotation of the drill stem for automatlcally actuating said valve means, said valve means having mechanism for enabling a predetermined feed table,

of the drill, independently of the automatic control.

7. In well drilling ap aratus, means for rotating a drill stem, hy raulic powermechanism for feeding the drill stem, valve means for governing said hydraulic feed. mechanism and means dependent on the speed of rotation of the drill stem for automat cally actuating said valve means, said valve means being readily disconnectible from said automatic control means. y

8. In well drilling ap aratus, means for rotating a drill stem, hy raulic power mechanism for feeding the drill stem, valve means for governing said hydraulic feed mechanism and means dependent on the s eed of rotation of the drill stem for automatically actuating said valve means, said valve means having a manually operable control and means for cou-' pling the automatic control to said "manual control in different selected positions of the manual control.

9. In well drilling apparatus, a rotary table, shafting for drivin the same, a speed governor driven from sai valve actuatable by said governor, a power cylinder for regulating feed of a drill stem shafting, a control rotated by the table and power connections from said valve to said power cylinder. 1

.10. In well drilling apparatus, a rotary table, shafting for driving the same, a speed governor driven from said shafting, a control valve actuatable by said governor, a power cylinder for regulating feed of a drill stem rotated by the table and power connections from-said valve to said power control valve having means for automatically effecting a predetermined feeding operation of the power cylinder.

11. In a well drillingapparatus, a rotary shafting for driving the same, a speed governor driven from said shafting, a control valve actuatable by said governor, a ower cylinder for regulating feed of a dril stem rotated by the table, power connections from said valve to said power cylinder, said concylinder, said trol valve having meansfor automatically effect-ing a predetermined feeding operation of the power cylinder and said control value being readily disconnectible from said governor.

12. In well drilling valve actuatable by said governor, a ower cylinder for regulating feed of a dril stem rotated by the table, power connections from said valve to said power cylinder, said-conapparatus, "a rotary table, shafting for driving the same, a speed governor driven from said shafting, a control governor driven from said shafting, a control valve actuatable by said governor, a lpower rof the power cylinder, means for connecting the governor and control valve in various different relations of the two, and an indi cator for gaging the relation of said parts with the rotary table for assisting in the coupling of the governor at the desired speed relation.

14. In well drilling apparatus, the combination with a rotary table and a power cylinder operable to variably feed the drill rotated by the table, of control means for said power feed mechanism adjustable to set the power mechanism for a predetermined normal rate of drill feed and an automatic device governed by the speed of rotation of the table and operable on the control means to cause the latter to effect slower or faster feed or return to normal feed in accordance with the formation encountered.

15. In well drilling apparatus, a rotary table, a power cylinder, connections actuated thereby for applying the lifting and lowering forces of said cylinder to a drill rotated by the table, a control valve operable to govern the effect of said power cylinder, and automatic means governed by the speed of rotation ofthe drill rotated by the table and connected with the valve to exercise control over said valve and to of the power cylinder.

16. In a well drilling apparatus, the combiwith the speed of the table rotation, said speed governor being connected to efiect operation of said control means and thereby cause the power mechanism to variably feed the control according to the speed of rotation of the table.

17. In well drilling apparatus, the combination with a rotary table and a power cylinder for variably feeding a drill rotated by the table, of control means for'said power feed mechanism adjustable to set the power mechanism for a predetermined normal rate of drill feed and an automatic power governor dependent for its operation upon the speed of rotation of the drill by the table, said governor being connected with the control means for advancing the setting of the same beyond that for the normal predetermined rate of drill feed to thereby advance the drill faster than permitted under the setting for nor- I mal feed when formation conditions entherebygovern the drill lifting and lowering efl'ect countered by the drill warrant faster feeding than what the control means is first set for. a

In witness whereof, I have hereunto set my hand this 30th day of Januar 1926.

y WALDO sHELDoN. 

